The influences of the moral and religious sanctions, or, in other words, of the motives of love of reputation and religion, are other causes, the force of which may, upon particular occasions, come to be greater than that of any punishment which the legislator is able, or at least which he will think proper, to apply. These, therefore, it will be proper for him to have his eye upon. But the force of these influences is variable and different in different times and places: the force of the foregoing influences is constant and the same, at all times and every where. These, therefore, it can never be proper to look upon as safe grounds for establishing absolute impunity: owing (as in the above-mentioned cases of infancy and intoxication) to the impracticability of ascertaining the matter of fact.
IPML Chapter 13 Section 3